Embodiments described herein relate to a structure for preventing contamination from a cut surface of dicing in a large scale integrated circuit chip and also relates to a large scale integrated circuit wafer that is mounted with a plurality of such large scale integrated circuit chips. In particular, the disclosure relates to a technique that can be effectively used in a display driver IC, for example.
Wafers such as silicon wafers are formed with a great number of chip forming regions by a specific semiconductor integrated circuit producing process, such as by a CMOS integrated circuit producing technology. Dicing regions are formed between the chip forming regions, and the chip forming regions are cut apart at the dicing regions into pieces to be used as large scale integrated circuit chips.
The large scale integrated circuit chips are usually inspected in the condition of being mounted on a large scale integrated circuit wafer before they are cut apart into pieces. To efficiently perform the inspection, external connection terminals that have the same function and that are formed in the respective chip forming regions may be commonly connected between the chip forming regions by test wirings provided in the dicing regions. The test wirings connect to test pads for signals or test pads for power source in the dicing regions. Thus, by pressing terminals of a test probe against the test pads, the large scale integrated circuits in the chip forming regions are inspected per wafer. Such test wirings and test pads are disclosed in WO 2010/110233, for example.
Dicing a large scale integrated circuit wafer may generate a crack due to stress that concentrates around a chip forming region. The crack that is generated around the periphery of the large scale integrated circuit chip facilitates entering of moisture from the outside. In view of this, as disclosed in JP-A-2012-89668, a guard ring (moisture resistant ring) may be provided to an outer periphery of a chip forming region so that entering of moisture can be prevented.